We review the jealousy literature and present our Dynamic Functional Model of Jealousy, which argues that jealousy evolved and has its own unique motivational state aimed at preventing others from usurping important relationships. It has a core form that exists in infants and nonhuman animals and an elaborated form in humans that emerges as cognitive sophistication develops. The DFMJ proposes that jealousy is an unfolding process with early and late phases that can be differentially impacted by relationship and personality factors. (...) It also notes the importance of looking at multiple concomitants of jealousy, including action tendencies. We discuss how jealousy fits with current emotion theories and suggest that theories of specific emotions need to be broadened. (shrink)